1. Field of the Invention
The present invention relates to a surface panel mounted on a mobile device or other electronic devices and including a decorative layer and a touch sensor portion. The present invention particularly relates to a surface panel that can secure a wide display region and a sensing region in which a touch sensor portion performs sensing, and to a method of manufacturing the surface panel.
2. Description of the Related Art
A surface panel mounted on a mobile device or other electronic devices has a transmissive region through which a display screen, such as a liquid crystal display panel, can be seen and on which a touch operation is digitally performed, in its center portion. A frame-shaped colored decorative portion is mounted on the periphery of the transmissive region.
In a surface panel and with a method of manufacturing the surface panel described in Domestic Re-publication of PCT International Publication for Patent Application No. WO2008/149789, a capacitive touch sensor is stacked on a back surface of a glass substrate via a transparent pressure sensitive adhesive layer. By placing the glass substrate in a mold and injecting a melted resin into the mold, a frame-shaped decorative portion made of a synthetic resin is fixedly attached to the periphery of the glass substrate.
In an outer casing and with a method of manufacturing the outer casing described in Japanese Unexamined Patent Application Publication No. 2009-130283, a first film and a second film are included. The first film includes a light transmissive portion, a frame-shaped decorative portion surrounding the light transmissive portion, and a touch display portion formed on part of the decorative portion. The second film has electrodes of a touch sensor formed thereon. After the first and second films are preformed so as to follow the outline of the outer casing, the first and second films are placed in a mold, and a transparent resin material is injected into a space between the first and second films, and molded. Thus, part of the outer casing is formed.
The surface panel according to Domestic Re-publication of PCT International Publication for Patent Application No. WO2008/149789 is advantageous in that the transmission quality of display light is favorable since a light transmissive region is formed by the glass substrate. However, since the surface panel includes the frame-shaped decorative portion made of a synthetic resin at the outer periphery of the glass substrate, the area of the light transmissive region and a sensing region, in which the touch sensor can perform sensing, is very small. Moreover, an injection molding has to be performed by positioning an assembly of the glass substrate and the touch sensor inside the mold. Thus, the method of manufacturing the surface panel is complex.
In the outer casing described in Japanese Unexamined Patent Application Publication No. 2009-130283, a touch sensor is disposed on a region that is different from a light transmissive portion. Thus, a user cannot perform an input operation by directly touching a display portion of the light transmissive portion with his/her finger. Moreover, since the light transmissive portion is disposed in a limited space on an upper side of the outer casing, a large screen cannot be displayed.
The method of manufacturing the surface panel according to Japanese Unexamined Patent Application Publication No. 2009-130283 involves two steps, which are a step of preforming the first and second films and a step of injecting a melted resin. Furthermore, the method is subject to limitation of accuracy of positioning the preformed first and second films inside the mold.